Support benchmarking of resident compilation #39
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| val command = new CompilerCommand(line split "\\s+" toList, new Settings(scalacError)) | ||
| compiler.reporter.reset() | ||
| new compiler.Run() compile command.files | ||
| } |
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the resident method seems to be unused
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can we get a breakdown of the time and memory usage changes on a phase by phase basis, as we have the instrumentation to support this |
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@mkeskells To integrate One approach would be to use |
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@retronym the -YprofileDestination should work for that that, recording a run sequence no as one of the columns in the standard csv output. Could do a custom recorder but need to work out what to do with GC |
Resident (aka, multi Run) compilation reuses a global, and its symbol table,
for subsequent compilation tasks.
Currently, this mode is only used in the presentation compiler and in the
REPL compiler.
This can lead to significant savings by avoiding re-parsing/-unpickling
class files. We'd expect this to matter more for small compile batches.
Resident compilation currently doesn't have a good for cache invalidation.
If a JAR or .class file is updated, it should throw away part of the symbol
table and re-read the classes.
The data we gather from these benchmarks will help motivate the effort to
add this cache invalidation.
It is also worth remembering that reducing the overhead of small compilation
batches is also useful for projects with large codebases. Zinc compiles small
sets of source files in an incremental compilation session.